Apparatus for detecting leaks in a pressurized air conditioning or refrigeration system

ABSTRACT

An apparatus ( 22 ) and method for detecting leaks in a pressurized air conditioning or refrigeration system ( 24 ) comprising a cartridge ( 26 ) is described. A facility ( 28 ) is for fluidly coupling the cartridge ( 26 ) to the pressurized system ( 24 ). An assemblage ( 30 ) is for forcing a secondary fluid ( 32 ) out of the cartridge ( 26 ), through the fluidly coupling facility ( 28 ) and into a service valve ( 34 ) of the pressurized system ( 24 ). The cartridge ( 26 ) has a first open end with an inner nozzle ( 33 ) which connects to the system being charged and an outer nozzle ( 37 ).

This application is a continuation-in-part of U.S. patent applicationSer. No. 09/535,368, filed Mar. 24, 2000, now pending, which is acontinuation of U.S. patent application Ser. No. 09/003,021, filed Jan.5, 1998, now U.S. Pat. No. 6,050,310, which is a continuation-in-part ofU.S. patent application Ser. No. 08/710,486, filed Sep. 18, 1996, nowU.S. Pat. No. 5,826,636, the entire contents of which are herebyincorporated by reference and relied upon.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The instant invention relates generally to the field of pressurizedfluid systems and more specifically it relates to an apparatus fordetecting leaks in a pressurized air conditioning or refrigerationsystem. The purpose of the apparatus is to provide the technician with asimple method of injecting a predetermined amount of a secondary fluid,e.g., a fluorescent dye, and/or lubricant into a pressurized system.

2. Description of the Prior Art

Numerous pressurized fluid systems have been provided in the prior artthat are adapted to operate optimally within a certain pressure range.If the internal pressure falls below this range, the system needs to berecharged with an appropriate lubricant. While these units may besuitable for the particular purpose to which they address, they wouldnot be as suitable for the purposes of the present invention asheretofore described.

There does not presently exist a cost effective way to accomplish thetask of inserting a predetermined amount of lubricant into a pressurizedsystem. Added to this, is the fact that when a technician arrives onsite they are faced with a myriad number of systems with serviceconnection access ranging from the accessible to the acrobatic and oftencramped working conditions.

Some systems contain a combination of fluids. For example, airconditioning and refrigeration systems generally contain a refrigerant(the primary fluid) in combination with a lubricating oil (the secondaryfluid) for the compressor and other critical components. The lubricatingoil is generally present in fairly low quantities, usually less than 5%of the total fluid. The present invention provides for the introductionof these and other secondary fluids into air conditioning orrefrigeration systems charged with the primary fluids in order to detectleaks in the pressurized systems.

Furthermore, air conditioning or refrigeration system leaks aredifficult to locate because refrigerants are generally odorless andcolorless gases. The present invention provides for a device and methodfor injecting a small amount of a concentrated fluorescent additive ordye into the system, thereby making the leaks easier to find. Thefluorescent dye can be injected into the system with the present deviceor they can be placed in the systems at the original equipmentmanufacturing facility prior to the system being put into service. Theseair conditioning and refrigeration systems are closed loop recirculatingsystems and the secondary fluid is a lubricant that also travelsthroughout the system while in operation. The dye will travel throughoutthe system and leak out with the refrigerant. The dye will leave a stainthat can be further enhanced with the use of an ultraviolet (UV) lamp.The UV wavelength of light will excite the dye allowing the operator tomore easily identify the exact location of the leak. The device can alsobe used to add the appropriate lubricant to the air conditioning orrefrigeration system without stopping the system and without any specialequipment.

A cartridge that is at or about atmospheric pressure while not in usecontains the concentrated fluorescent dye and/or lubricant. Thecartridge is connected to the device of the present invention in a waythat will raise the pressure of the dye above that of the operatingsystem. The connection between the device and the operating system mustbe airtight. The connection can be a quick coupler, thread or othermeans of positive, sealed connection.

SUMMARY OF THE INVENTION

The preferred embodiment of the present invention is for an apparatusfor detecting leaks in a pressurized air conditioning or refrigerationsystem and includes an injection device with a receptacle portion forreceiving a disposable or reusable lubricant canister and a connectorassembly for attaching the lubricant canister to the pressurized system.The lubricant canister contains lubricant and/or fluorescent dye. It isa further aim of the present invention not to limit the mechanical meansof lubricant and/or fluorescent dye delivery just to hand pressure, butto provide other embodiments using various types of hand tools andstructures to accomplish the delivery of the lubricant and/orfluorescent dye to the pressurized system.

More specifically, the present invention is for an apparatus fordetecting leaks in a pressurized air conditioning or refrigerationsystem, comprising a canister containing a secondary fluid, where thesecondary fluid comprises a fluorescent dye; means for fluidly couplingthe canister to the pressurized system; and means for forcing thesecondary fluid out of the canister, through the fluidly coupling meansand into a service valve of the pressurized system.

In a preferred embodiment, the canister includes a tubular casing forholding the secondary fluid therein; a threaded nozzle integral with andextending out from a first end of the tubular casing to engage with oneend of the fluidly coupling means; and a piston inserted within an opensecond end of the tubular casing to engage with a secondary fluidforcing means.

In a more preferred embodiment, the tubular casing is fabricated out oftransparent material and includes a plurality of gradient markings toaid in accurately dispensing a predetermined amount of the secondaryfluid therefrom. In another embodiment, the canister further includes athreaded cap, to engage with the threaded nozzle when the canister isnot in use, so as to prevent leakage of the secondary fluid through thethreaded nozzle.

In another preferred embodiment, the fluidly coupling means is aconnector assembly having a first end connected to the threaded nozzleof the canister and a second end connected to the service valve of thepressurized system. In a more preferred embodiment, the connectorassembly includes a flexible conduit; a thread on the first end of theflexible conduit, to engage with the threaded nozzle of the canister;and a release valve on a second end of the flexible conduit, to engagewith the service valve of the pressurized system.

In another preferred embodiment, the connector assembly further includesa one-way check valve at the first end of the flexible conduit, whichprevents any material from back flushing into and contaminating thesecondary fluid in the canister.

In yet another preferred embodiment, the release valve includes acloseable valve, which prevents any material from back flushing into theflexible conduit from the service valve of the pressurized system, andto allow the release valve to disconnect from the service valve of thepressurized system, to prevent leakage of the secondary fluid therefrom.

In more preferred embodiments, the release valve includes a snap lockfitting to engage with the service valve of the pressurized system orincludes a threaded fitting, to engage with the service valve of thepressurized system.

In another more preferred embodiment, the secondary fluid forcing meansis an injection device. In yet another more preferred embodiment, theinjection device includes a housing having a receptacle portion toreceive the canister therein; and a drive mechanism to force the pistoninto the tubular casing, to cause the secondary fluid to exit thethreaded nozzle through the fluidly coupling means, past the servicevalve and into the pressurized system.

In another preferred embodiment, the drive mechanism includes a handgrip integral with and extending downwardly on the housing; a triggerpivotally mounted to the housing adjacent the hand grip; a central driveshaft extending longitudinally through the housing and transversely pasta pivotal portion of the trigger; a cylindrical head on an inner end ofthe central drive shaft, to engage with the piston of the canister; afirst pawl spring biased on the central drive shaft forward the pivotalportion of the trigger; and a second pawl spring biased on the centraldrive shaft rearward the pivotal portion of the trigger, the second pawlhaving a tongue extending out through a rear wall of the housing abovethe hand grip, so that when the trigger is squeezed, the first pawl willmove into contact with the central drive shaft, to push the centraldrive shaft forward with the cylindrical head making contact with thepiston, while the second pawl prevents reverse movement of the centraldrive shaft, until the tongue disengages the second pawl, allowing thecentral drive shaft to be pulled back to a desired position.

In a more preferred embodiment, the drive mechanism includes a hand gripintegral with and extending downwardly on the housing; a triggerpivotally mounted to the housing adjacent the hand grip; a central driveshaft extending longitudinally through the housing and transverselyabove a pivotal portion of the trigger, the central drive shaft having aplurality of teeth extending therealong; a cylindrical head on an innerend of the central drive shaft, to engage with the piston of thecanister; and a pawl pivotally mounted between the pivotal portion ofthe trigger and the housing, so that when the trigger is squeezed, thepawl will move into contact with the teeth on the central drive shaft,to push the central drive shaft forward with the cylindrical head makingcontact with the piston.

In another more preferred embodiment, the drive mechanism includes asecond pawl spring biased in the housing to make contact with the teethon the central drive shaft forward the first pawl, to prevent reversemovement of the central drive shaft.

In yet another more preferred embodiment, the drive mechanism includes astationary nut mounted vertically within a rear wall of the housing; anelongated threaded rod extending longitudinally through the stationarynut; a cylindrical head on an inner end of the elongated threaded rod,to engage with the piston of the canister; and means on an outer end ofthe elongated threaded rod for rotating the elongated threaded rodthrough the stationary nut and moving the elongated threaded rod withthe cylindrical head forward, to make contact with the piston.

In another preferred embodiments, the rotating means is a bolt headwhich can be turned by an open end and box wrench, is a socket headwhich can be turned by a ratchet socket wrench or is a handle rodextending transversely through the outer end of the elongated threadedrod which can be turned by a hand of a person.

In another preferred embodiment, the drive mechanism includes a rearchamber formed within the housing and having an inlet port to allowcompressed gas to enter the rear chamber; a central drive shaft carriedlongitudinally within the tubular casing of the canister; a cylindricalhead on an inner end of the central drive shaft, to engage with thepiston; and a transverse drive plate on an outer end of the centraldrive shaft within the tubular casing adjacent the rear chamber, so thatwhen the compressed gas is introduced through the inlet port into therear chamber, the transverse drive plate will push the central driveshaft forward with the cylindrical head to make contact with the piston.

The present invention also discloses a canister or cartridge forcharging a closed, pressurized air conditioning or refrigeration systemwith a fluid. The cartridge comprises a closed, non-pressurizedcylindrical cartridge, where the cartridge has two ends, a first openend and a second open end, where the first open end comprises an innernozzle which connects to the system being charged and an outer nozzle; apredetermined amount of the fluid; and a piston sealably disposed withthe second open end of the cartridge, where the cartridge is adapted toconnect sealably and releasably to the pressurized air conditioning orrefrigeration system to form a closed binary system.

In preferred embodiments of the cartridge, the fluid comprises alubricant for the air conditioning or refrigeration systems; the fluidcomprises a fluid dye for the air conditioning or refrigeration systems;or the fluid comprises a lubricant and a fluid dye for the airconditioning or refrigeration systems.

In other preferred embodiments of the cartridge, the fluid is maintainedin the cartridge at about ambient pressure; and/or the cartridge isfabricated out of transparent material and includes a plurality ofgradient markings.

In yet other preferred embodiments of the cartridge, the inner nozzle issurrounded by an internal thread; the outer nozzle is surrounded by anexternal thread; the outer nozzle comprises a threaded cap forengagement with the external thread; and/or the inner nozzle issurrounded by an internal thread and the outer nozzle is surrounded byan external thread.

In still other preferred embodiments of the cartridge, the pistonfurther comprises an O-ring; or the piston further comprises a recesseddouble O-ring.

The present invention also discloses a method for detecting leaks in apressurized air conditioning or refrigeration system. The methodcomprises the steps of charging the pressurized air conditioning orrefrigeration system with a fluorescent dye with the apparatus of thepresent invention; inspecting the pressurized air conditioning orrefrigeration system for leaks of the fluorescent dye from thepressurized air conditioning or refrigeration system; and detecting anyleaks in the pressurized air conditioning or refrigeration system. In apreferred embodiment, the inspecting is done with ultraviolet light.

Thus, a primary object of the present invention is to provide anapparatus for detecting leaks in a pressurized air conditioning orrefrigeration system that will overcome the shortcomings of the priorart devices.

Another object is to provide an apparatus for detecting leaks in apressurized air conditioning or refrigeration system that will allow atechnician to inject a predetermined amount of lubricant and/orfluorescent dye into the pressurized system.

It is yet a further object of the invention to provide a method andapparatus for charging a pressurized air conditioning/refrigeration linewith a lubricant and/or fluorescent dye from a closed, non-pressurizedcharging cartridge containing a predetermined amount of such lubricantand/or fluorescent dye.

An additional object is to provide an apparatus for detecting leaks in apressurized air conditioning or refrigeration system which can bereadily carried to a site, be easily operated, and can deliver ameasured amount of lubricant and/or fluorescent dye into the pressurizedsystem.

A further object is to provide an apparatus for detecting leaks in apressurized air conditioning or refrigeration system that is simple andeasy to use.

A still further object is to provide an apparatus for detecting leaks ina pressurized air conditioning or refrigeration system that iseconomical in cost to manufacture.

It is yet a further object to present an apparatus and method fordetecting leaks in air conditioning or refrigeration systems byinjecting a fluorescent dye into the systems and then inspecting thesystem for leaks of the fluorescent dye from the systems.

Further objects of the invention will appear as the descriptionproceeds.

To the accomplishment of the above and related objects, this inventionmay be embodied in the form illustrated in the accompanying drawings,attention being called tot he fact, however, that the drawings areillustrative only, and that changes may be made in the specificconstruction illustrated and described within the scope of the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Various other objects, features and attendant advantages of the presentinvention will become more fully appreciated as the same becomes betterunderstood when considered in conjunction with the accompanyingdrawings, in which like reference characters designate the same orsimilar parts throughout the several views, and wherein;

FIG. 1 is a side view of a first embodiment of the present invention.

FIG. 2 is an enlarged side view of the injection device shown in FIG. 1.

FIG. 3 is a cross sectional view taken along line 3—3 in FIG. 2.

FIG. 4 is an enlarged side of the lubricant canister in FIG. 1.

FIG. 5 is a cross sectional view taken along line 5—5 in FIG. 4.

FIG. 6 is a side view of the connector assembly in FIG. 1.

FIG. 7 is a top view taken in the direction of arrow 7 in FIG. 6.

FIG. 8 is an end view taken in the direction of arrow 8 in FIG. 6.

FIG. 9 is a side view of a second embodiment of the connector assembly.

FIG. 10 is an end view taken in the direction of arrow 10 in FIG. 9.

FIG. 11 is a top view taken in the direction of arrow 11 in FIG. 9.

FIG. 12 a perspective view of a second embodiment of the injectiondevice.

FIG. 13 is a cross sectional view taken along line 13—13 in FIG. 12.

FIG. 14 is an enlarged cross sectional view of an area in FIG. 13 asindicated by arrow 14.

FIG. 15 is a cross sectional view similar to FIG. 13, showing a singlepawl mechanism to propel the toothed central shaft in the injectiondevice.

FIG. 16 is a perspective view of a third embodiment of the injectiondevice.

FIG. 17 is a cross sectional view taken along line 17—17 in FIG. 16.

FIG. 18 is a perspective view similar to FIG. 16, showing a socketwrench to turn the operating screw in the injection device.

FIG. 19 is a perspective view similar to FIG. 18, showing a transversehandle to turn the operating screw in the injection device.

FIG. 20 is a cross sectional view of a fourth embodiment of theinjection device, whereby compressed gas is introduced within a chamberto drive the piston forward in the lubricant canister.

FIGS. 21A-F show a preferred embodiment of the cartridge of the presentinvention. FIG. 21A is a front view of the cartridge. FIG. 21B is a backview of the cartridge. FIGS. 21C and 21D are the left and right sideview, respectively, of the cartridge. FIG. 21E is a top view and FIG.21F is a bottom view of the cartridge.

Similar reference characters denote corresponding features consistentlythroughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now descriptively to the drawings, in which similar referencecharacters denote similar elements throughout the several views, FIG. 1illustrates the present invention being an apparatus 22 for detectingleaks in a pressurized air conditioning or refrigeration system 24. Withregard to the reference numerals used, the following numbering is usedthroughout the various drawing figures.

22 charging apparatus

24 pressurized system

26 canister of 22

28 fluidly coupling facility of 22

30 lubricant or secondary fluid forcing assemblage of 22

32 lubricant and/or fluorescent dye of 26

33 central nipple or inner nozzle

34 service valve of 24

35 internal thread

36 tubular casing of 26

37 outer nozzle

38 threaded nozzle of 26 on 36

39 external thread

40 piston of 26 in 36

42 transparent material for 36

44 gradient marking on 36

46 threaded cap of 26 on 38

47 connector assembly for 28

48 flexible conduit of 47

50 threaded fitting of 47 on 48

52 release valve of 47 on 48

54 one-way check valve of 47

56 closeable control knob or valve of 52

58 snap lock fitting of 52

60 threaded fitting of 52

62 injection device for 30

64 housing of 62

66 receptacle portion of 64

68 drive mechanism of 30

70 hand grip of 68

72 trigger of 68

74 central drive shaft of 68

76 cylindrical head of 68 on 74

78 first pawl of 64

80 spring of 78

82 second pawl of 64

84 spring of 82

86 tongue of 82

88 teeth on 74

90 first pawl pivotally mounted between 72 and 64

92 second pawl on 64

94 stationary nut of 68

96 elongated threaded rod of 68

98 rotating structure of 68 on 96

100 bolt head for 98

102 open and wrench

104 socket head for 98

106 ratchet socket wrench

108 handle rod for 98

110 rear chamber of 68 in 64

112 inlet port of 110

114 transverse drive plate of 68

The apparatus 22 for detecting leaks in a pressurized air conditioningor refrigeration system 24 comprises a lubricant canister 26. A facility28 is for fluidly coupling the lubricant canister 26 to the pressurizedsystem 24. An assemblage 30 is for forcing lubricant and/or fluorescentdye 32 out of the lubricant canister 26, through the fluidly couplingfacility 28 and into a service valve 34 of the pressurized system 24.

The lubricant canister or cartridge 26, as shown in FIGS. 1, 4, 5, 13,14, 15, 17 and 20 includes a tubular casing 36 for holding the lubricantand/or fluorescent dye 32 therein. A threaded nozzle 38 is integral withand extends out from a first end of the tubular casing 36, to engagewith one end of the fluidly coupling facility 28. A piston 40 isinserted within an open second end of the tubular casing 36, to engagewith the lubricant forcing assemblage 30.

The tubular casing 36 can be fabricated out of transparent material 42and can include a plurality of gradient markings 44, to aid inaccurately dispensing a predetermined amount of the lubricant and/orfluorescent dye 32 therefrom. The lubricant canister 26 further includesa threaded cap 46, as shown in FIGS. 4 and 5, to engage with thethreaded nozzle 38 when the lubricant canister 26 is not in use, so asto prevent leakage of the lubricant and/or fluorescent dye 32 throughthe threaded nozzle 38.

In a preferred embodiment of the lubricant canister or cartridge 26, asshown in FIG. 21, a central nipple or inner nozzle 33 is integral withand extends out from the first end of the tubular casing 36, to engagewith one end of the fluidly coupling facility 28. The central nipple orinner nozzle 33 is surrounded by an internal thread 35 to facilitateengagement with one end of the fluidly coupling facility 28. Thelubricant canister or cartridge 26 further includes an outer nozzle 37surrounded by an external thread 39 to engage with a threaded cap whenthe lubricant canister 26 is not in use, so as to prevent leakage of thelubricant and/or fluorescent dye 32 through the threaded nozzle. Theexternal threads 39 are fitted for a drip cap with a standard size.

In practice, the central nipple or inner nozzle 33 can be made to extendslightly beyond the end of the outer nozzle 37. A cap with an inductionseal, which seals on the central nipple or inner nozzle 33, can be used.These caps are lined with tinfoil, so that a heated, sealed end resultswhich is able to withstand pressure and which seals directly to thelubricant or dye, if there is any present.

The design of the internal thread 35 allows a threaded check valve tomate with and to force the sealing area down the central nipple or innernozzle 33. The central nipple 33 is tapered slightly to allow easyinstallation and sealing with an O-ring on the inside of the check valveof the fluidly coupling facility 28 and seals to the outsidecircumference of the central nipple. This design results in a very costeffective and quick connect and disconnect mating system. The system hasbeen designed to be one single turn for full connection. The seal thatis formed is capable of withstanding very high pressures (300+psi) withvery little operator effort for connecting and disconnecting.

The external threads 39 allow the operator to cap the device with anairtight seal for disposal or when not in use. The cartridge can befabricated out of transparent material 42 and can include a plurality ofgradient markings 44, to aid in accurately dispensing a predeterminedamount of the lubricant and/or fluorescent dye 32 therefrom. Thelubricant canister 26 may further include a piston sealed therein. Thepiston may be made without any O-rings and uses pressure to further sealon the bore.

Furthermore, the design of the fluidly coupling facility 28 and themating central nipple 33 ensures that only a minimal amount of fluid isleft behind when the connection is disengaged. The fluorescent dye isvery concentrated and expensive. In some applications, as little as twoml of fluid is injected per air conditioning or refrigeration systembeing tested so minimizing fluid loss is critical to the effectivenessof the diagnostic method.

The fluidly coupling facility 28, as shown in FIGS. 1 and 6 through 11,is a connector assembly 47 having a first end connected to the threadednozzle 38 of the lubricant canister 26 and a second end connected to theservice valve 34 of the pressurized system 24. The connector assembly 47consists of a flexible conduit 48. A threaded fitting 50 is on the firstend of the flexible conduit 48, to engage with the threaded nozzle 38 ofthe lubricant canister 26. A release valve 52 is on the second end ofthe flexible conduit 48, to engage with the service valve 34 of thepressurized system 24.

The connector assembly 47 further includes a one-way check valve 54between the threaded fitting 50 and the first end of the flexibleconduit 48, which prevents any material from back flushing into andcontaminating the lubricant and/or fluorescent dye 32 in the lubricantcanister 26. The release valve 52 contains a closeable control knob orvalve 56, which prevents any material from back flushing into theflexible conduit 48 from the service valve 34 of the pressurized system24, and allows the release valve 52 to disconnect from the service valve34 of the pressurized system 24, to prevent leakage of the lubricantand/or fluorescent dye 32 therefrom.

The release valve 52 in FIGS. 1, 6, 7 and 8, includes a snap lockfitting 58 to engage with the service valve 34 of the pressurized system24. The release valve 52 in FIGS. 9, 10 and 11, includes a threadedfitting 60, to engage with the service valve 34 of the pressurizedsystem 24.

The lubricant forcing assemblage 30, as shown in FIGS. 1 to 3 and 12 to20, is an injection device 62. The injection device 62 contains ahousing 64 having a receptacle portion 66, to receive the lubricantcanister 26 therein. A drive mechanism 68 forces the O-ring piston 40into the tubular casing 36, to cause the lubricant and/or fluorescentdye 32 to exit the threaded nozzle 38 through the fluidly couplingfacility 28, past the service valve 34 and into the pressurized system24.

The drive mechanism 68 in FIGS. 1 to 3 includes a hand grip 70 integralwith and extending downwardly on the housing 64. A trigger 72 ispivotally mounted to the housing 64 adjacent the handgrip 70. A centraldrive shaft 74 extends longitudinally through the housing 64 andtransversely past a pivotal portion of the trigger 72. A cylindricalhead 76 is on an inner end of the central drive shaft 74, to engage withthe O-ring piston 40 of the lubricant canister 26.

A first pawl 78 is spring biased at 80 on the central drive shaft 74forward the pivotal portion of the trigger 72. A second pawl 82 isspring biased at 84 on the central drive shaft 74 rearward the pivotalportion of the trigger 72. The second pawl 82 has a tongue 86 extendingout through a rear wall of the housing 64 above the handgrip 70. Whenthe trigger 72 is squeezed the first pawl 78 will move into contact withthe central drive shaft 74, to push the central drive shaft 74 forwardwith the cylindrical head 76 making contact with the recessed O-ringpiston 40. The second pawl 82 prevents reverse movement of the centraldrive shaft 74, until the tongue 86 is lifted up to disengage the secondpawl 82, allowing the central drive shaft 74 to be pulled back to adesired position.

The drive mechanism 68 in FIGS. 12 to 15 includes a hand grip 70integral with and extending downwardly on the housing 64. A trigger 72is pivotally mounted to the housing 64 adjacent the handgrip 70. Acentral drive shaft 74 extends longitudinally through the housing 64 andtransversely above a pivotal portion of the trigger 72. The centraldrive shaft 74 has a plurality of teeth 88 extending therealong. Acylindrical head 76 is on an inner end of the central drive shaft 74, toengage with the O-ring piston 40 of the lubricant canister 26.

A pawl 90 is pivotally mounted between the pivotal portion of thetrigger 72 and the housing 64. When the trigger 72 is squeezed, the pawl90 will move into contact with the teeth 88 on the central drive shaft74, to push the central drive shaft 74 forward with the cylindrical head76 making contact with the O-ring piston 40. As best seen in FIGS. 13and 14, the drive mechanism 68 can include a second pawl 92 springbiased in the housing 64 to make contact with the teeth 88 on thecentral drive shaft 74 forward the first pawl 90, to prevent reversemovement of the central drive shaft 74.

The drive mechanism 68 in FIGS. 16 to 19 includes a stationary nut 94mounted vertically within a rear wall of the housing 64. An elongatedthreaded rod 96 extends longitudinally through the stationary nut 94. Acylindrical head 76 on an inner end of the elongated threaded rod 96engages with the O-ring piston 40 of the lubricant canister 26. Astructure 98 on an outer end of the elongated threaded rod 96 is forrotating the elongated threaded rod 96 through the stationary nut 94 andmoves the elongated threaded rod 96 with the cylindrical head 76forward, to make contact with the O-ring piston 40.

The rotating structure 98 in FIGS. 16 and 17 is a bolt head 100, whichcan be turned by an open end or box wrench 102. The rotating structure98 in FIG. 18 is a socket head 104, which can be turned by a ratchetsocket wrench 106. The rotating structure 98 in FIG. 19 is a handle rod108 extending transversely through the outer end of the elongatedthreaded rod 96, which can be turned by a hand of a person.

The drive mechanism 68, shown in FIG. 20, includes a rear chamber 110formed within the housing 64 and has an inlet port 112 to allowcompressed gas to enter the rear chamber 110. A central drive shaft 74is carried longitudinally within the tubular casing 36 of the lubricantcanister 26. A cylindrical head 76 is on an inner end of the centraldrive shaft 74 to engage with the O-ring piston 40. A transverse driveplate 114 is on an outer end of the central drive shaft 74 within thetubular casing 36 adjacent the rear chamber 110. When the compressed gasis introduced through the inlet port 112 into the rear chamber 110, thetransverse drive plate 114 will push the central drive shaft 74 forwardwith the cylindrical head 76, to make contact with the O-ring piston 40.

Thus, the present invention provides for a device and method forinjecting a small amount of a concentrated fluorescent additive or dyeinto the system, thereby making any leaks easier to find. Thefluorescent dye can be injected into the system with the present deviceor they can be placed in the systems at the original equipmentmanufacturing facility prior to the system being put into service. Theseair conditioning and refrigeration systems are closed loop recirculatingsystems and the secondary fluid is a lubricant that also travelsthroughout the system while in operation. The dye will travel throughoutthe system and leak out with the refrigerant. The dye will leave a stainthat can be further enhanced with the use of an ultraviolet (UV) lamp.The UV wavelength of light will excite the dye allowing the operator tomore easily identify the exact location of the leak. The device can alsobe used to add the appropriate lubricant to the air conditioning orrefrigeration system without stopping the system and without any specialequipment.

Finally, a cartridge that is at or about atmospheric pressure while notin use contains the concentrated fluorescent dye and/or lubricant. Thecartridge is connected to the device of the present invention in a waythat will raise the pressure of the dye above that of the operatingsystem. The connection between the device and the operating system mustbe airtight. The connection can be a quick coupler, thread or othermeans of positive, sealed connection.

It will be understood that each of the elements described above, or twoor more together may also find a useful application in other types ofmethods differing from the type describe above.

While certain novel features of this invention have been shown anddescribed are pointed out in the annexed claims, it is not intended tobe limited to the details above, since it will be understood thatvarious omissions, modifications, substitutions and changes in the formsand details of the device illustrated and in its operation can be madeby those skilled in the art without departing in any way from the spiritof the present invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this invention.

What is claimed is:
 1. A cartridge for charging a closed, pressurizedair conditioning or refrigeration system with a fluid, comprising: a) aclosed, non-pressurized cylindrical cartridge, wherein the cartridge hastwo ends, a first open end and a second open end, wherein the first openend comprises an inner nozzle which connects to the system being chargedand an outer nozzle; b) a predetermined amount of the fluid; and c) apiston sealably disposed with the second open end of the cartridge,wherein the cartridge is adapted to connect sealably and releasably tothe pressurized air conditioning or refrigeration system via fluidlycoupling means to form a closed binary system, wherein the fluidlycoupling means is a connector assembly having a first end connected tothe inner nozzle of the cartridge and a second end connected to aservice valve of the pressurized system, wherein the connector assemblycomprises: i) a flexible conduit, ii) a thread on a first end of theflexible conduit, to engage with the inner nozzle of the cartridge, andiii) a release valve on a second end of the flexible conduit, to engagewith the service valve of the pressurized system, and wherein theconnector assembly further comprises a valve at one end of the flexibleconduit, which prevents any material from back flushing into andcontaminating the fluid in the cartridge.
 2. The cartridge of claim 1,wherein the fluid comprises a lubricant for the air conditioning orrefrigeration system.
 3. The cartridge of claim 1, wherein the fluidcomprises a fluid dye for the air conditioning or refrigeration system.4. The cartridge of claim 1, wherein the fluid comprises a lubricant anda fluid dye for the air conditioning or refrigeration system.
 5. Thecartridge of claim 1, wherein the fluid is maintained in the cartridgeat about ambient pressure.
 6. The cartridge of claim 1, wherein thecartridge is fabricated out of transparent material and includes aplurality of gradient markings.
 7. The cartridge of claim 1, wherein theinner nozzle is surrounded by an internal thread.
 8. The cartridge ofclaim 1, wherein the outer nozzle is surrounded by an external thread.9. The cartridge of claim 8, wherein the outer nozzle comprises athreaded cap for engagement with the external thread.
 10. The cartridgeof claim 1, wherein the inner nozzle is surrounded by an internal threadand wherein the outer nozzle is surrounded by an external thread. 11.The cartridge of claim 1, wherein the piston further comprises anO-ring.
 12. The cartridge of claim 1, wherein the piston furthercomprises a recessed double O-ring.